Seasonal Rainfall Patterns in Australia

The rainfall pattern is strongly seasonal in character with a winter
rainfall regime in the south and a summer regime in the north. Uniform
rainfall occurs in much of New South Wales, parts of eastern Victoria and
southern Tasmania. The monsoonal rains or the extreme north fall between
November and March and are often unreliable.

More than 80% of the continent has at least three months each year that
are without effective precipitation.